Baghdad bomb:A bomb in a car parked outside a kebab restaurant in the mostly Shiite commercial district of Karradah in central Baghdad killed at least three people, U.S. and Iraqi officials said.

BAGHDAD – The number of Iraqi security forces killed in September rose by nearly one-third to 159 compared with the same period last year, Associated Press figures showed yesterday. U.S. troop deaths for the same period fell by nearly 40 percent to 25.

The figures are a sign that the U.S. military is increasingly relying on the Iraqis, including U.S.-allied Sunni fighters, to take the lead in operations so they can assume responsibility for security and let U.S. forces eventually withdraw.

Overall civilian casualty figures remained relatively low despite a spate of deadly attacks in Baghdad and surrounding areas during the Islamic fasting month of Ramadan, which ended yesterday for Sunnis and ends tomorrow for most Shiites.

But even as Iraqi security forces are taking the lead and violence in the country has plunged 80 percent over the past 15 months, cautious Pentagon leaders have resisted calls for more rapid and hefty troop pullouts. Instead, top commanders insist the security situation remains fragile and the improvements reversible.

One potential source of conflict comes this week, when the Shiite-led government begins to assume authority over tens of thousands of Sunni fighters who turned against al-Qaeda in Iraq.

Six U.S. Army brigades, a National Guard unit and three military headquarters have been ordered to deploy to Iraq next summer, the Pentagon announced yesterday, in a move that would allow the United States to keep the number of troops largely steady there through much of next year.

The planned deployments involve about 26,000 troops and would maintain 14 combat brigades in Iraq from about February to early fall.